Control of automobile motors.



Z ATENTEI) FEB. 6, 1906.

LE MOTURS.

APPLICATION FILED mm: 29

OONTRGL 5F AUTOM'QBI F F F F m r r F F m m up m B m m BM W m m .M 9 F FF R lnven'for Edward H.Ander 0n BM m 6 7 00 g 9 m F Ru F Wihwsws u WMUNITED STATES PATENT orruon.

EDWARD H. ANDERSON,

OF SGHENECTADY, NEW YORK, ASSIGNOR TO GENERAL ELECTRIC COMPANY, ACORPORATION or NEW YORK.

Specification of Letters Patent.

Patented Feb. 6, 1906.

Application filed June 29, 1905. Serial No. 267,510.

trol of Automobile Motors, of which the following is a specification.

The present invention relates to means for controlling the operation andspeed of electric motors, and more particularly single motors employedfor propelling automobiles or the like.

It has heretofore been the practice in single-motor drives forautomobiles, wherein acceleration and speed-changes are-eiiected throughvariation of the resistance in the motor-circuit and of the relativeconnection of the motor-windings, to open the motorcircuit as anintermediate step inthe making of a change in the circuit connections.It is evident that the opening of the motor-circuit, if but for aninstant, takes away the torque of the motor. When the circuit is againcompleted and the tor ue established, the motor runs free until all thelost motion in the driving connection is taken up, whereupon itdehversahammer-blow to the driven part and jerks the vehicle onward. This jerkyaction is not only extremely disagree-' able to the occupants, but isalso injurious to the mechanism. Aside from the objections to theirregular propellin action of the motor the breaking and ma 'ng of themotorcircuits, whenever a change in the motor-circuit is to be effected,is injurious to the battery and reduces its efficiency byreason of thesudden rush of current which takes place up on the making of thecircuit. If the torque is materially diminished in making transitions,then, even though the motor-circuit be not entirely interrupted, thejerky action is produced.

The object of the present invention is to provide a system of controlfor a single motor of the character specified, so arranged that thevarious speed-changes may be efiected without interrupting the circuitand without materially reducing the tor us of the motor. The presentinventionwil be more clearly understood from the following descriptionthereof and of the preferred means for canrying[ it out.

n the accompanying drawings, Figure 1 illustrates diagrammatically amotor and a controller arranged and connected in accordance with thepresent invention, and Figs. 2 to 8 indicate the circuit conditionscorresponding to various portions of" the controller.

In the systemillustrated the motor has two series field-windings, andthe control apparatus is arranged to provide five running speeds,although as to these features modifications may of course be made. A isthe motorarmature. F and F are the fieldwindings. B is the storagebattery. Risa resistance, and C is a controller.

The controller is shown as consisting of a developed cylinder havingsegments d (1 and e 6 which comprise movable contacts, together with arow of fingers c c, which cooperate with the segmental contacts. Thecontacts (1 al control the motor for driving the vehicle forward, andthe contacts e e are brought into play for reversin These two groups ofcontacts may be aike except in that they change the relative connectionof the field-windings to the armature. However, it is not necessary torunthe motor at high speeds in'reversing the vehicle, so that the numberof running positions may be reduced to one or two.

Referring to Fig. 1, it will be seen that on turning the controller soas to brin the movable contacts into engagement wit the fixed fingersalong line 1 a circuit is completed from one terminal of the batterythrough the motor-armature, throughthe resistance, R, through contact 0,contacts (1' and d fieldwinding F, contact 0 contacts d (Z and 0?,field-winding F, contact 0, and thenceto the opposite terminal of thebattery'through contacts d d, and 0 The motor-circuit is now as shown inFig. 2 and the motoris running at its lowest speed. Upon turning thecontroller to osition 2 no change is produced except that t e resistanceR is short-circuited at contacts 0 and c, d and d, the motor being nowconnected as shown in Fig. 3 and the motor running at an increasedspeed. When the controller is moved to position 3, contact (1 comes intoen agement with contactand the current a ter it leaves the armatureinstead of assing wholly through the field-windings an back to thebattery now passes in the part through section r of the resistance R,through contacts 0 d, d d and 0 to the batterynan iely, the resistance'1' is shunted about the field-windings. as illus trated in Fig. 4. Lesscurrent now passes through the field-windings than in thepreviousposition of the controller. Therefore the motor runs at anincreased speed.

In order to obtain the next highest speed, the shunt is removed and thefield-windings are connected in parallel, this being accomplished bymeans of a series of operations, which take place as the controller ismoved from position 3 to position 4namely, in position 3 finger cengages simultaneously with contact (i and d whereby the current insteadof flowing from contact 0 through field-winding F and thence tofield-winding F through contacts 0* and 0 now flows from contact 0through contacts d and (Z directly to contact 0 short-circuitingfield-winding F. The short-circuiting connection is made, how- .ever,without interruptirrg the circuit of the motor. In position 3* segmentat has left contact c and segment d" has left contact therebydisconnecting field-winding F and opening the shunt containing theresistance r, the circuit being now as shown in Fig. 6. Inposition 4 ofthe controller segimmto" engages with finger c and current flows throughthe field-windings in parallelnamely, from finger c a circuit passesthrough the movable contacts (I d, thence through contact 0'',field-windings 1*", and to the battery, and another circuit passes fromcontact 0 through the movable contacts (1 (1 through contact c throughthe field- Winding F and thence to the battery through contact 0, d, d,and c". In the linal position of the controller contact d engages withcontact 0 and the shunt, including the resistance r, is again placedabout the fieldwindings, as illustrated in Fig. 8, giving a weaker fieldthan before, and consequently an increased speed.

It is noted that'at no time is the motor-circuit interrupted after thecontroller has been moved to its first running position until it isagain returned to its otl position. 'lhus the motor at no time loses itstorque, but is always exerting a propelling effort. It is also seen thatthe armature-current is not reduced during the change from series toparallel, and therefore the torque does not decrease, thereby insuringthat the propelling efiort shall be smooth and comfortable.

It is evident that the resistance 1 instead of being a portion of theresistance R maybe an entirely separate and independent resistance.

Although I have described the present in vention in the preferred form,I do not desire to be limited to the particular form illustrated exceptto the extent indicated in the accompanying claims.

That I claim as new, and desire to secure by Letters Patent of theUnited States, is-

1 In a single-motor drive for automobiles, a storage battery, a motorprovided with a lurality' of field-windings, and a controller liavingcontacts arranged and connect-ed to connect said motor to said batterywith the field-windings in series, shunt one of the fieldwindings,remove said shunted field-winding without breaking the shunt, and thenconnect the field-windings in parallel.

2. In a single-motor drive for automobiles, a source of current-supply,a motor having two field-windings, a resistance, and a controller havingcontacts arranged to connect said motor to said source of current-supplywith the field-windings in series with each other, then connect saidfield-windings in parallel with said resistance, then shunt one of saidfield-windings, then remove said resistance and cut out said latterfield-winding without opening the shunt and finally connect the idlefield-winding in parallel with the remaining field-winding.

3. In a single-motor drive for automobiles, a source of current-supply,a motor having two tield windings, a resistance, and a controllerlntvinga plurality of running positions and contacts arranged to connect saidmotor to said source of current-supply with its fieldwindings in seriesin one position of the controller, to place said resistance in parallelwith the tieldwindings in a second position, to remove said resistanceand connect the field-windings in parallel in a thirdposition, and tofirst place a shunt about one of said field-windings and then disconnectsaid latter field-winding without breaking the shunt in passing from thesecond to the third positron.

In witness whereof I have hereunto hand this 27th day of June, 1905.

El)\VAHD H, ANDERSON. l/Vitnesses:

BENJAMIN B. HULL, HELEN Oaroan.

set my

